Outside drill-pipe cutter



April 1929- J. M CULLOUGH OUTSIDE DRILL PIPE CUTTER Filed July 28, 1926 fra J Mafia/yr? ATTORNEYS.

R m m m Patented Apr. 16 1929.

UNITED STATES IRA J. HcCULLOUG-H, OF WALNUT PARK, CALIFORNIA.

OUTSIDE DRILL-PIPE CUTTER.

Application filed July 28, 1926. Serial No. 125,564.-

This invention relates to a tool for severing pipes, casing, and like tubular members, and pertains more particularly to a tool which may be passed over the outside of the pipe.

It is often desirable and sometimes necessary to cut pipe which has become lodged in a well hole. The present invention is adapted for use in such cases, and is operable by placing it over a pipe and lowering it to a position where the cut is to be made.

It is the primary object of this invention to provide a tool of the character described which includes cutters arranged to be set out of severing position and so lowered over the pipe, then to be released to severing position by manipulation of the tool over the pipe. These objects together with other objects and corresponding accomplishments are obtained by means of the embodiment of my invention illustrated in v the accompanying drawing, in which Fig. 1 is an axial section through a cutter with the blades in retracted position, the tool being shown disposed over a fragment of a string of pipe, the latter being shown in elevation; Fig. 2 is an axial section as seen on a plane at right angles toFig. 1, the blades being released; Fig. 3 is a section as seen upon the line 3-3 ofFig. 2; Fig. lis an elevation of the blade actuator element; Fig. 5 is an elevation of the finger lock ring; and Fig. 6 is a section as seen on the line 6-6 of Fig. 2.

Referring with more particularity to the drawing, 7 indicates a drill pipe, a fragment thereof being shown and provided with a coupling 8. This is the pipe to be operated upon and severed. The cutter is passed over the pipe and lowered to position.

The cutter proper is secured to the lower end of a wash pipe 9. It comprises a blade actuator 10 secured to the lower end of the wash pipe and a shell 11 provided with a shoe guide at its lower-end. Slidably mounted within the shell is a blade carrier 12, andbelow the blade carrier is an arrester or feed ring 13.

The actuator comprises a tubular body having a bore internally threaded at the top so that it may be secured to the wash pipe 9. The lower portion is reduced in diameter and externally threaded as indicated by 14. De-

pending from the body are wedge members 15 equal in number to the number of knives or blades used. In this particular instance,

- there are three wedge members shown equally spaced, and each having one of its edges straight. The blade carrier comprises a ring 16 having openings in the periphery in which are mounted blades 17 on axially disposed plvots, so that they may be swung either inwardly to retracted position or projected laterally outwardly. To accommodate full passage of the actuator wedges, slots 18 are provided in the blade rings. The carrier is slidably mounted in the shell 11 so that it may be moved longitudinally.

Supporting the blade carrier is an arrester comprising an arrester ring 13 having secured thereto spring fingers 19 extending downwardly with the ends tending to press inwardly against the pipe. On the shell 11 is secured a stop ring 20. The carrier may have a llmited longitudinal movement between arrester 13 and the actuator. The fingers 19 have their ends curved inwardly as indicated by 21 so as to be engageable with a re cess in a lock ring 22. The lockring has an upper outer recess 23 to receive the ends of the spring fingers. It is also provided with an annular recess 24 having a slot 25 formed therein so as to provide a bayonet connection. In the shell are rivets 26 adapted to be disposed in the recess 24. Upstanding from the lock ring are short spring fingers'27 bent inwardly.

The parts are so arranged that they may be slipped over the drill pipe string 7 clearing the coupling. In placing the cutter in position, it is lowered with the parts in the position shown in Fig. 1. When the cutter has been located at the point it is desired to cut the pipe, it is raised upwardly, the fingers 27 on a lock ring engaging the under side of the coupling just above and arresting movement, the fingers forming a one-way pipe gripping means and frictionally engaging the coupling so as to retain the latter against being turned. The cutter is then turned to register the rlvets or pins 26 with the slots 25 thereby releasing the lock ring and allowing it to seat on the abutment rin 28 of the shell in the position shown in 2. The spring fingers 19 may then be pulled from the lock ring recess 23 by raising the tool, fingers 27 holding ring 22. The lower ends of fingers 19 are spaced from the upper ends of fingers 27 a distance less than the height of a pipe coupling. This insures the ends of fingers 19 resting against the periphery ofthe coupling when the upper ends of fingers 27 engage the lower edge of the couplin The tool may then be lowered to permit 51c ends of fingers 19 to pass below the coupling, or the cutter may be raised to a positlon such that the spring fingers 19 are above the coupling, this may cause a crushing of the spring fingers 27 on the lock ring in order to permit the latter to pass the coupling. When the tips of fingers 19 have been positioned beyond the coupling, the tool is lowered until the tips engage the next lower coupling. The fingers 19 support the arrester ring 13 and blade carrier 16, maintaining them station- .ary upon thefstring. However, the wedges cutter carrier being movable toward said actuator for operation thereby, an arrester to support said carrier for operative engagement with said actuator and having one way abutment means engageable with a string of pipe, and lock means for said arrester to hold the latter in inoperative position, said-lock means being releasable by abutment with the string of pipe.

2. In a cutter of the character described, a body for encompassing a pipe, a cutter carrier mounted therein for limited longitudinal movement, said carrier having cutters laterally projectable toward the pipe to be cut, a cutter actuator secured to said body for projecting said cutters, an arrester within said body to stop the movement of said carrier whereby said actuator maybe caused to project said cutters, and lock means foriholding said arrester in inoperative position, said lock means being operable to release said arrester by upward movement of said body and engagement with a pipe coupling.-

' 3. In a cutter of the character described,

a body for embracing a pipe to be cut, a cut ter carrier mounted therein for limited longitudinal movement, said carrier having cutters laterally projectable toward the pipe, a cutter actuator secured to said body for projecting said cutters, an arrester within said body for supporting said carrier, said arrester? including one way pipe gripping means, and a lock means to hold said grip r 4 ping means in inoperative position, said lock means having one way pipe engaging means whereby to release said grip means.

4. In a cutter of the character described, a body for embracinga pipe to be cut, a cut- 5. Inacutter of the character described,

a body tor embracing a pipe to be out, a cutter carrier mounted thereon for limited lon gitudinal movement, said carrier having cutters laterally projectable toward the pipe, a L

. cutter actuator secured to said body, an arrester Within said body for supporting said carrier, said arrester including inwardly urged spring fingers, a lock ring to hold said fingers out of engagement with the pipe, said lock ring having inwardly urged spring fingers for engaging said pipe, means for holding said lock ring to said body releasable by rotation of the latter.

6. In a cutter of the character described, a body for embracing a pipe to be cut, a cutter carrier mounted thereon for limited longitudinal movement, said carrier having cutters peripherally arranged and laterally projectable toward the pipe, a cutter actuator secured to said body having wedges dependenttherefrom for engagement with said cutters to project the'latter, an arrester within said body for supporting said carrier, said arrester including one wayv pipe gripping ,means, and a lock means to hold said gripping means in inoperative position, said lock means having one way pipe engaging means whereby to release said gripping means.

7. In a cutter of the character described, a body for embracing a pipe to be cut, a cutter carrier-mounted thereon for limited longitudinal movement, said carrier having cutters eripherally arranged and laterally projecta le toward the pipe, a cutter actuator secured to said body having depending wedges for engaging said cutters and projecting the latter, an arrester within said body for supporting said carrier, said ar-- day of July, 1926.

IRA J. MCCULLOUGH. 

